Fiducial deployment mechanisms, and related methods of use

ABSTRACT

A medical device that may include an elongate member having a proximal end and a distal end, and a lumen disposed through the elongate member is disclosed. The medical device may also include an opening disposed at the distal end of the elongate member in communication with the lumen, and a pushing element disposed with the lumen. The medical device may also include at least one fiducial disposed within the lumen and distal to the pushing element, and a separating mechanism disposed at the distal end of the elongate member. The separating mechanism may be configured to apply a separating force to deploy the at least one fiducial.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority of U.S. ProvisionalApplication No. 61/834,235, filed Jun. 12, 2013, the entirety of whichis incorporated by reference herein.

TECHNICAL FIELD

Various embodiments of the present disclosure relate generally tomedical devices and related systems and methods. More specifically, thepresent disclosure relates to devices, systems, and methods fordeploying fiducials.

BACKGROUND

Endosonographers use Endoscopic Ultrasound Fine Needle Aspiration (EUSFNA) for diagnosis and staging of disease. EUS FNA is a highly effectivediagnostic procedure. An ultrasound image generated by EUS FNA allows aphysician to visualize the position of a needle in relation to a targetand surrounding tissue structures. This aids in ensuring that thecorrect tissue is sampled and that the risk to the patient is minimized.

However, therapeutic tools and procedures for endosonographers are lesswell established. Current industry trends and research are focusing ondevelopment of devices that would enable endosonographers to treatspecific conditions once diagnosis has been established.

One area currently being explored for EUS guided therapy is theplacement of fiducials. Fiducials act as markers so diseased tissue canbe targeted for more effective delivery of radiation or othertreatments. Currently, the fiducial placement is a very time consumingprocedure for the endosonographers. It generally requires the physicianto load and place the markers one at a time.

SUMMARY

The present disclosure includes devices, systems, and methods fordeploying fiducials, for example, during an EUS FNA procedure.

In accordance with an embodiment, the present disclosure is directed toa medical device. The medical device may include an elongate memberhaving a proximal end and a distal end, and a lumen disposed through theelongate member. The medical device may also include an opening disposedat the distal end of the elongate member in communication with thelumen, and a pushing element disposed with the lumen. The medical devicemay also include at least one fiducial disposed within the lumen anddistal to the pushing element, and a separating mechanism disposed atthe distal end of the elongate member. The separating mechanism may beconfigured to apply a separating force to deploy the at least onefiducial.

Various embodiments of the disclosure may include one or more of thefollowing aspects: wherein the at least one fiducial may be one of aplurality of fiducials disposed within the lumen and connected to eachother by a linkage; wherein the separating mechanism may be configuredto direct the separating force to a distal portion of the linkage todeploy a distalmost fiducial; wherein the at least one fiducial may beone of a plurality of fiducials disposed within the lumen, and adjacentfiducials may be disposed within compartments separated by spacers; andwherein the separating mechanism may be configured to apply theseparating force to a distalmost spacer to deploy a distalmost fiducial.

In accordance with an embodiment, the present disclosure is directed toa method of deploying multiple fiducials within a patient. The methodmay include advancing a medical device into a body lumen of the patient,and applying a distally-directed force to direct at least one fiducialtoward an opening at a distal end of the medical device. The method mayalso include applying a separating force, distinct from thedistally-directed force, to deploy the fiducial.

Various embodiments of the disclosure may include one or more of thefollowing aspects: wherein the distally-directed force may be applied bya pushing element disposed within a lumen of the medical device; whereinthe separating force may be one of an electric charge, heat, or amechanical force; wherein the at least one fiducial may be one of aplurality of fiducials connected to each other by a linkage, and themethod may further include applying the separating force to a distalportion of the linkage to deploy a distal fiducial; wherein the at leastone fiducial may be one of a plurality of fiducials disposed within thelumen, and adjacent fiducials may be disposed within compartmentsseparated by spacers, and the method may further include applying theseparating force to a distalmost spacer to deploy a distalmost fiducial;and applying the separating force to a distal end of a continuous lengthof fiducial material to form a plurality of fiducials.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a first lumendisposed through the elongate member. The method device may also includean opening disposed at the distal end of the elongate member incommunication with the lumen, and a plurality of fiducials disposedwithin the first lumen. The medical device may also include at least onebiasing element disposed within the first lumen proximal to theplurality of fiducials. The biasing element may be configured to urgethe plurality of fiducials toward the opening after deployment of adistalmost fiducial.

Various embodiments of the disclosure may include one or more of thefollowing aspects: a distal opening mechanism disposed at the distal endof the elongate member, the distal opening mechanism configured torotate about a joint to eject a distalmost fiducial from the firstlumen; and a second lumen may be disposed in the elongate memberparallel to the first lumen, and a pushing element may be disposedthrough the second lumen, the pushing element being configured toreciprocally move between a proximal loading position and a distaldeployment position, wherein when the pushing element is in the proximalloading position and no fiducial is in the second lumen, a distalmostfiducial disposed within the first lumen is urged toward the secondlumen.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a lumen disposedthrough the elongate member. The medical device may also include anopening disposed at the distal end of the elongate member incommunication with the lumen, and a plurality of fiducials disposeddistal to the pushing element. The medical device may also include apull wire having a distal protrusion being disposed distal to adistalmost fiducial of the plurality of fiducials and configured toretain the plurality of fiducials within the lumen.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a lumen disposedthrough the elongate member. The medical device may also include anopening disposed at the distal end of the elongate member incommunication with the lumen, and a plurality of fiducials disposeddistal to the pushing element, each of the plurality of fiducials havinga protrusion. The medical device may also include a groove disposed on aside surface of the elongate member that receives the protrusion of eachof the plurality of fiducials.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a lumen disposedthrough the elongate member. The medical device may also include anopening disposed at the distal end of the elongate member incommunication with the lumen, and a plurality of fiducials disposedwithin the lumen. The medical device may also include a pushing elementconfigured to direct the plurality of fiducials through the opening, anda liquid disposed between adjacent fiducials.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a lumen disposedthrough the elongate member. The medical device may also include anopening disposed at the distal end of the elongate member incommunication with the lumen, and a cartridge disposed at the distal endof the elongate member distal to the pushing element. The cartridge mayhave a plurality of chambers disposed radially about the cartridge. Themedical device may also include a plurality of fiducials disposed withinthe plurality of chambers.

In accordance with an embodiment, the present disclosure is directedtoward a medical device. The medical device may include an elongatemember having a proximal end and a distal end, and a lumen disposedthrough the elongate member. The medical device may also include anopening disposed at the distal end of the elongate member incommunication with the lumen, and a plurality of fiducials disposedwithin the lumen. The medical device may also include an actuatordisposed at a proximal end of the elongate member. The actuator mayinclude a cap having a distal projection. The medical device may alsoinclude a plurality of seats configured to couple with the distalprojection. Adjacent seats of the plurality of seats may be transposedabout the longitudinal axis of the elongate member, and the longitudinaldistance between adjacent seats may correspond to the longitudinaldistance moved by the actuator to deploy a single fiducial of theplurality of fiducials.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate various exemplary embodiments andtogether with the description, serve to explain the principles of thedisclosed embodiments.

FIG. 1 is a side perspective view of a medical device in accordance withan embodiment of the present disclosure.

FIGS. 2-6 are partial side cross-sectional views of deploymentmechanisms in accordance with various embodiments of the presentdisclosure.

FIG. 7 is a side perspective view of a medical device in accordance withan embodiment of the present disclosure.

FIGS. 8-9 are partial side cross-sectional views of deploymentmechanisms in accordance with various embodiments of the presentdisclosure.

FIGS. 10-11 are partial side cross-sectional views of a deploymentmechanism in accordance with an embodiment of the present disclosure.

FIG. 12 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure.

FIG. 13 is a top plan view of a cartridge used in conjunction with thedeployment mechanism of FIG. 12.

FIGS. 14-15 are partial side perspective views of exemplary actuators inaccordance with various embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments of the presentdisclosure, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

As shown in FIG. 1, a medical device 100 according to an exemplaryembodiment of the present disclosure may include a first needle 102 anda second needle 104 connectable to one another. A further example of asuitable medical device includes that described in U.S. PatentApplication Publication 2011/0196258, published on Aug. 11, 2011, theentire disclosure of which is incorporated by reference herein. Firstneedle 102 may include a first longitudinal element 106 defining a lumen(not shown). First longitudinal element 106 may be flexible such thatfirst longitudinal element 106 may be inserted into the body along atortuous path (e.g., within a body lumen) to reach a target area withinthe body.

A proximal end of first longitudinal element 106 may be coupled to afirst handle 116 sized to slidably receive first longitudinal element106. First handle 116 may further include a luer fitting 122 forcoupling to the second needle 104. Second longitudinal element 108 mayextend longitudinally from a proximal end to a distal end and include alumen (not shown). An outer diameter of second longitudinal element 108may be smaller than an inner diameter of the first lumen of firstlongitudinal element 106 such that second longitudinal element 108 maybe slidably inserted through the first lumen. For example, in oneembodiment, first longitudinal element 106 may be a 19 gauge needlewhile second longitudinal element 108 may be a 22 gauge needle.Alternatively, first longitudinal element 106 may be a 22 gauge needlewhile second longitudinal element 108 may be a 25 gauge needle.

A length of second longitudinal element 108 may be longer than a lengthof first longitudinal element 106 such that when the second longitudinalelement 108 is inserted into the first lumen, the distal end of thesecond longitudinal element 108 may be extended distally past the distalend of the first longitudinal element 106. The proximal end of thesecond longitudinal element 108 may include an actuator 140.

A second handle 130 may be attached to the proximal end of secondlongitudinal element 108. The distal end of the second handle 130 mayinclude a coupling element 138 adapted and configured to mate with theluer fitting 122 of first needle 102 such that first and second needles102, 104 may be connected to one another.

Second longitudinal element 108 of second needle 104 may be insertedthrough the lumen of first longitudinal element 106 of first needle 102such that second longitudinal element 108 is “nested” within firstlongitudinal element 106. Second longitudinal element 108 may be slidthrough the lumen of first longitudinal element 106 until couplingelement 138 of second needle 104 comes into contact with luer fitting122 of first needle 102.

FIG. 2 shows a partial side cross-sectional view of a medical device 200for deploying fiducials in accordance with an embodiment of the presentdisclosure. Medical device 200 may include an elongate member 202 havinga proximal end 204 and a distal end 206. The elongate member 202 may beinserted into a lumen of a patient's body to access a target sitewhereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 204 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 200. In some embodiments, medical device 200 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 208 may be disposed within a lumen 210 defined byelongate member 202. Pushing element 208 may be coupled to actuator 140in any suitable manner. Pushing element 208 may be advanced distally byactuator 140 and may contact a fiducial 212 disposed within lumen 210. Aplurality of fiducials 212 may be disposed along a longitudinal axis oflumen 210 and may be connected to each other by a linkage 214. Linkage214 may extend within and between the plurality of fiducials 212.Linkage 214 may be a wire, suture, or other suitable linkage. Fiducials212 may include a generally radiopaque material so that targeted regionsof a patient's body may be located by ultrasound or other suitableimaging techniques. Fiducials 212 may likewise include a porous, pitted,angled, rough, or irregular surface in order to improve visibility underultrasound or other suitable imaging techniques, including by providingstructures on the surface(s) of the fiducial 212. Fiducials 212 mayinclude gold or another suitable metal. In some embodiments, fiducials212 may further include compliant materials. In one embodiment,fiducials 212 may be spherical, although any other suitable shape alsomay be utilized, including shapes selected to improve visibility underultrasound, e.g. polygonal. In an alternative embodiment, fiducials 212may include substance-eluting (e.g., drug-eluting) materials. Fiducials212 may likewise be configured for placement at a desired region of apatient's body, including by implantation on, within, or underneathtissue at a targeted region of a patient's body by piercing, cutting, orseparating tissue at the desired region, or by adhering the fiducial 212to the tissue by, e.g., providing an adhesive coating or pattern on thesurface of fiducial 212.

A separating mechanism 216 may be disposed at distal end 206 of medicaldevice 200. Separating mechanism 216 may be configured to disintegrateor otherwise sever linkage 214 between consecutive fiducials 212. In oneexemplary embodiment, as pushing element 208 is moved distally (e.g., byactuator 140), a distalmost fiducial 212 may extend distally out oflumen 210 via an opening 218. In an alternative embodiment, elongatemember 202 may be moved proximally (while pushing member 208 is held inplace) to eject the distalmost fiducial 212 out of lumen 210. In yetanother alternative embodiment, pushing element 208 may be coupled tolinkage 214, and both pushing element 208 and linkage 214 may be movedproximally such that a distalmost end of linkage 214 is removed from thedistalmost fiducial 212, releasing the distalmost fiducial 212.

In one embodiment, once a distalmost linkage 214 is within an effectiverange of separating mechanism 216, separating mechanism 216 may generatea separating force to deploy a distalmost fiducial 212. In oneembodiment, separating mechanism 216 may emit an electrical charge thatdisintegrates or severs a distalmost portion of linkage 214. Currentcarrying wires (not shown) may extend through medical device 200 toproximal end 204, where they may be coupled to, e.g., an RF generator orother suitable mechanism. An actuator (not shown) may be disposed atproximal end 204 that may be activated to cause current to flow alongthe current carrying wires and across opening 218 to separate fiducials212. In an alternative embodiment, separating mechanism 216 may directheat toward linkage 214, thereby melting linkage 214 and releasing thedistalmost fiducial 212. It should be noted, however, that otheralternative separating mechanisms utilizing electrical, mechanical,and/or chemical mechanism are also contemplated.

FIG. 3 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 300 may include an elongate member 302 having a proximal end 304and a distal end 306. Similar to elongate member 202, elongate member302 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 304 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 300. In some embodiments, medical device 300 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

Elongate member 302 may be a needle defined by a first lumen 308 and asecond lumen 310 that are parallel to each other and separated by a wall312. Elongate member 302 may include a tapered section 314 disposedpartway around the circumference of elongate member 302 that extendsfrom an intermediate portion of elongate member 302 toward an opening316 disposed at distal end 306. A biasing element 318 may be disposed infirst lumen 308 and may be located proximally to a loading zone 320configured to hold a plurality of fiducials 322. Loading zone 320 maythus be defined by biasing element 318, wall 312, tapered section 314,and an inner portion of elongate member 302. In one embodiment, biasingelement 318 may be a coiled spring. Alternatively, biasing element 318may be any suitable structure capable of providing a biasing forceincluding, but not limited to, other compressible materials.

A pushing element 324 may be disposed within second lumen 310 and may becapable of reciprocal movement to load and eject fiducials 322 one at atime from elongate member 302. As shown in FIG. 3, pushing element 324may be in an intermediate position, where a fiducial 322 is in a loadedposition distal to the distal end of pushing element 324. Pushingelement 324 may be moved distally toward opening 316 to eject a loadedfiducial out of elongate member 302. In a fully extended position, thedistal end of pushing element 324 may be coplanar with opening 316 orproximal to opening 316. Alternatively, the distal end of pushingelement 324 may extend through opening 316 to deploy fiducials 322.After deployment of a fiducial 322, pushing element 324 may be retractedto a loading position represented by reference axis A-A (i.e., alocation that is proximal to a distalmost fiducial 322 within firstlumen 308). That is, pushing element 324 may be retracted so that itsdistal end is located generally along axis A-A, and a distalmostfiducial 322 located in loading zone 320 may be laterally urged bybiasing element 318 and tapered section 314 toward second lumen 310 andthe distal end of pushing element 324. After loading of a fiducial 322,pushing element 324 may be returned to the intermediate position.

FIG. 4 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 400 may include an elongate member 402 having a proximal end 404and a distal end 406. Similar to elongate member 202, elongate member402 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 404 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 2), for operating themedical device 400. In some embodiments, medical device 400 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 408 may be disposed within a lumen 410 defined byelongate member 402. Pushing element 408 may be coupled to actuator 140in any suitable manner. Pushing element 408 may be advanced distally byactuator 140 and may contact a fiducial 412 disposed within lumen 410. Aplurality of fiducials 412 may be disposed along a longitudinal axis oflumen 410. Fiducials 412 may be substantially similar to fiducials 212(referring to FIG. 2), but may be shaped such that fiducials 412 areretained in lumen 410 absent a compressing force applied to them. In oneembodiment, at least one diameter of fiducials 412 is greater than thediameters of both a tapered section 413 and an opening 414 disposed atdistal end 406 of elongate member 402. Fiducials 412 may be conical,though any other suitable shape is also contemplated including, but notlimited to spherical, ovular, rectangular, asymmetrical, or the like.Tapered section 413 may be an interference fit taper section thatextends entirely around a circumference of elongate member 402 thatdefines opening 414. In an alternative embodiment, instead of having asmaller diameter than a remaining portion of elongate member 402,tapered section 413 may have substantially the same diameter as theremaining portion of elongate member 402 but also include inwardprotrusions that reduce an effective diameter of lumen 410 at taperedsection 413. Fiducials 412 may include a compliant material such thatfiducials 412 are contained within lumen 410. That is, a compressingforce may be applied to fiducials 412, reducing the effective diameterof fiducials 412 to enable them to eject from elongate member 402 viatapered section 413 and opening 414 (i.e., fiducials 412 may snapthrough tapered section 413 and opening 414 when a sufficientcompressive and distally-directed force is applied). In an alternativeembodiment, elongate member 402 may be moved proximally (while pushingmember 408 is held in place) to apply the compressing force to adistalmost fiducial 412, enabling it to eject out of lumen 410.

FIG. 5 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 500 may include an elongate member 502 having a proximal end 504and a distal end 506. Similar to elongate member 202, elongate member502 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 504 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 500. In some embodiments, medical device 500 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 508 may be disposed within a lumen 510 defined byelongate member 502. Pushing element 508 may be coupled to actuator 140in any suitable manner. Pushing element 508 may be advanced distally byactuator 140 and may contact a fiducial 512 disposed within lumen 510. Aplurality of fiducials 512 may be disposed along a longitudinal axis oflumen 510. Fiducials 512 may be substantially similar to fiducials 412(referring to FIG. 4), but may be shaped such that fiducials 512 arecontained by a projection 514 extending from a pull wire 516 disposedwithin lumen 510. Similar to pushing element 508, pull wire 516 may becoupled to actuator 140 or a similar mechanism. In one embodiment,fiducials 512 may be conical, though any other suitable shape is alsocontemplated including, but not limited to spherical, ovular,rectangular, asymmetrical, or the like. Fiducials 512 may include acompliant material and may be contained within lumen 510 by projection514 unless a sufficient compressing force is applied. That is,projection 514 may be sized to inhibit the distal movement of fiducials512. To deploy a distalmost fiducial 512, pull wire 516 may be retractedproximally so that projection 514 is proximal to the distalmost fiducial512. Then, pushing element 508 may be directed distally to ejectdistalmost fiducial 512 out of lumen 510 via an opening 518. In analternative embodiment, elongate member 502 may be moved proximally(while pushing member 508 is held in place) to eject the distalmostfiducial 512 out of lumen 510. It should also be noted that asprojection 514 is moved proximal to the distalmost fiducial 512,projection 514 may secure (inhibit the distal movement of) a proximallyadjacent fiducial 512 in place for a subsequent deployment.

FIG. 6 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 600 may include an elongate member 602 having a proximal end 604and a distal end 606. Similar to elongate member 202, elongate member602 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 604 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 600. In some embodiments, medical device 600 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 608 may be disposed within a lumen 610 defined byelongate member 602. Pushing element 608 may be coupled to actuator 140in any suitable manner. Pushing element 608 may be advanced distally byactuator 140 and may contact a fiducial 612 disposed within lumen 610. Aplurality of fiducials 612 may be disposed along a longitudinal axis oflumen 610. Fiducials 612 may be substantially similar to fiducials 212(referring to FIG. 2), but also include a first seal 614 and a secondseal 616. Both first seal 614 and second seal 616 may be disposed arounda periphery of fiducials 612. Adjacent fiducials 612 may be separated bya liquid volume 617 (e.g., saline) to promote separation and ease ofdeployment. Further, the presence of liquid volume 617 between adjacentfiducials 612 may reduce the formation of air pockets within a patient'sbody during deployment of fiducials 612, improving the clarity of imagesgenerated by ultrasound and other imaging techniques. In one exemplaryembodiment, as pushing element 608 is moved distally (e.g., by actuator140 of FIG. 1), a distalmost fiducial 612 may extend distally out oflumen 610 via an opening 618. In an alternative embodiment, elongatemember 602 may be moved proximally (while pushing member 608 is held inplace) to eject a distalmost fiducial 612 out of lumen 610. First andsecond seals 614, 616 may be 0-rings or similar structures, and may havematerial properties that permit them to “roll” along the inside of lumen610 with its corresponding fiducial 612. Thus, as fiducials 612 aremoved distally, liquid volume 617 may be maintained between adjacentfiducials 612.

FIG. 7 is a partial side perspective view of a deployment mechanism inaccordance with an embodiment of the present disclosure. A medicaldevice 700 may include an elongate member 702 having a proximal end 704and a distal end 706. Similar to elongate member 202, elongate member702 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 704 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 700. In some embodiments, medical device 700 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 708 may be disposed within a lumen 710 defined byelongate member 702. Pushing element 708 may be coupled to actuator 140in any suitable manner. Pushing element 708 may be advanced distally byactuator 140 and may contact a fiducial 712 disposed within lumen 710. Aplurality of fiducials 712 may be disposed along a longitudinal axis oflumen 710. Fiducials 712 may be substantially similar to fiducials 212(referring to FIG. 2), but also include a protrusion 714 extending froma longitudinal surface of each fiducial 712. Protrusions 714 may bearranged within lumen 710 such that protrusions 714 are disposed withina groove 716 disposed within a longitudinal surface of elongate member702. That is, as fiducials 712 move distally through lumen 710,protrusions 714 may promote proper orientation and deployment offiducials 712 via its interaction with groove 716. Further, protrusions714 may act as retention elements, preventing deployment of fiducials712 unless a sufficient compressing and distally-directed force isapplied by pushing element 708. Protrusions 714 and/or fiducials 712 maybe compressible to facilitate deployment of fiducials 712. Groove 716may extend from a first longitudinal point to a second longitudinalpoint along the longitudinal axis of elongate member 702, though othersuitable configurations are also contemplated. For example, in onealternative embodiment, groove 716 may extend to proximal end 704 and/ordistal end 706 of elongate member 702. In one exemplary embodiment, aspushing element 708 is moved distally (e.g., by actuator 140 of FIG. 1),a distalmost fiducial 712 may extend distally out of lumen 710 via anopening 718. In an alternative embodiment, elongate member 702 may bemoved proximally (while pushing member 708 is held in place) to ejectthe distalmost fiducial 712 out of lumen 710. It is also contemplatedthat elongate member 702 may include a tapered section to retainfiducials 712 within lumen 710.

FIG. 8 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 800 may include an elongate member 802 having a proximal end 804and a distal end 806. Similar to elongate member 202, elongate member802 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 804 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 800. In some embodiments, medical device 800 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 808 may be disposed within a lumen 810 defined byelongate member 802. Pushing element 808 may be coupled to actuator 140in any suitable manner. Pushing element 808 may be advanced distally byactuator 140 and may contact a spacer 811 disposed within lumen 810. Aplurality of fiducials 812 may be disposed in compartments along alongitudinal axis of lumen 810 between adjacent spacers 811. Fiducials812 may be substantially similar to fiducials 212 (referring to FIG. 2).

A separating mechanism 816 may be disposed at distal end 806 of medicaldevice 800. Separating mechanism 816 may be substantially similar toseparating mechanism 216 (referring to FIG. 2) and may be configured todisintegrate or otherwise sever spacers 811 between consecutivefiducials 812. In one exemplary embodiment, as pushing element 808 ismoved distally (e.g., by actuator 140 of FIG. 1), a distalmost spacer811 may extend distally toward an opening 818 disposed at distal end 806of elongate member 802. In an alternative embodiment, elongate member802 may be moved proximally (while pushing member 808 is held in place)to direct the distalmost spacer 811 toward distal end 806.

In one embodiment, once a distalmost spacer 811 is within an effectiverange of separating mechanism 816, separating mechanism 816 may generatea separating force to deploy a distalmost fiducial 812. In oneembodiment, separating mechanism 816 may emit an electrical charge thatsevers spacer 811. In an alternative embodiment, separating mechanism816 may direct heat toward spacer 811, thereby melting spacer 811 andreleasing the distalmost fiducial 812. It should be noted, however, thatother alternative separating mechanisms utilizing electrical,mechanical, and/or chemical mechanism are also contemplated.

FIG. 9 is a partial side cross-sectional view of a deployment mechanismin accordance with an embodiment of the present disclosure. A medicaldevice 900 may include an elongate member 902 having a proximal end 904and a distal end 906. Similar to elongate member 202, elongate member902 may be inserted into a lumen of a patient's body to access a targetsite whereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 904 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 900. In some embodiments, medical device 900 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 908 may be disposed within a lumen 910 defined byelongate member 902. Pushing element 908 may be coupled to actuator 140in any suitable manner. Pushing element 908 may be advanced distally byactuator 140 and may contact a fiducial source 911 disposed within lumen910. Fiducial source 911 may be a continuous length of fiducial materialconfigured to be formed into a plurality of individual fiducials 912.Fiducials 912 may be substantially similar to fiducials 212 (referringto FIG. 2).

A separating mechanism 916 may be disposed at distal end 906 of medicaldevice 900. Separating mechanism 916 may be substantially similar toseparating mechanism 216 (referring to FIG. 2) and may be configured toform individual fiducials 912 from fiducial source 911, e.g., by theapplication of an electric charge, heat, or mechanical force. In oneexemplary embodiment, as pushing element 908 is moved distally (e.g., byactuator 140 of FIG. 1), a distal end of fiducial source 911 may extenddistally toward an opening 918 disposed at distal end 906 of elongatemember 902. In an alternative embodiment, elongate member 902 may bemoved proximally (while pushing member 908 is held in place) to direct adistal end of fiducial source 911 toward distal end 906.

In one embodiment, once fiducial source 911 has been distally advanced asufficient amount, separating mechanism 916 may generate a separatingforce to form a distalmost fiducial 912. The distal advancement can bemeasured at the proximal end by movement of pushing member 908. In oneembodiment, an actuator may also be a ratchet or other like mechanism atthe proximal end to permit incremental advancement of pushing member908. That is, in each increment, the actuator may move pushing member908 a predetermined amount to deploy one or more fiducials 912. In oneembodiment, separating mechanism 916 may emit an electrical charge thatsevers fiducial source 911 at a distal region to generate an individualfiducial 912. In an alternative embodiment, separating mechanism 916 maydirect heat toward fiducial source 911, thereby generating and releasinga newly formed distalmost fiducial 912. It should be noted, however,that other alternative separating mechanisms utilizing electrical,mechanical, and/or chemical mechanisms are also contemplated.

FIGS. 10-11 are partial side cross-sectional views of a deploymentmechanism in accordance with an embodiment of the present disclosure. Amedical device 1000 may include an elongate member 1002 having aproximal end 1004 and a distal end 1006. Similar to elongate member 202,elongate member 1002 may be inserted into a lumen of a patient's body toaccess a target site whereupon a medical or diagnostic procedure, suchas EUS FNA, is performed. The proximal end 1004 may be coupled to anactuating mechanism, such as actuator 140 (referring to FIG. 1), foroperating the medical device 1000. In some embodiments, medical device1000 may represent the distal end of second longitudinal element 108(referring to FIG. 1).

A biasing element 1008 may be disposed within a lumen 1010 defined byelongate member 1002. Biasing element 1008 may be coupled to a pluralityof stacked fiducials 1012 disposed within lumen 1010. A distal openingmechanism 1013 may include a cap 1014 coupled to an arm 1016 via ajoint/pivot pin 1018. Fiducials 1012 may be substantially similar tofiducials 212 (referring to FIG. 2). In one embodiment, biasing element1008 may be a coiled spring. Alternatively, biasing element 1008 may beany suitable structure capable of providing a biasing force including,but not limited to, other compressible materials.

To deploy a distalmost fiducial 1012, cap 1014 may be rotated aboutjoint 1018 such that arm 1016 ejects the distalmost fiducial 1012 fromlumen 1010 via an opening 1020. After a fiducial 1012 has been ejected,biasing element 1008 may urge a next distalmost fiducial 1012 to thedistalmost position. Cap 1014 may be actuated at the proximal end via apull wire (not shown) that couples cap 1013 to actuator 140 (referringto FIG. 1).

FIGS. 12-13 depict a deployment mechanism in accordance with anembodiment of the present disclosure. A medical device 1200 may includean elongate member 1202 having a proximal end 1204 and a distal end1206. Similar to elongate member 202, elongate member 1202 may beinserted into a lumen of a patient's body to access a target sitewhereupon a medical or diagnostic procedure, such as EUS FNA, isperformed. The proximal end 1204 may be coupled to an actuatingmechanism, such as actuator 140 (referring to FIG. 1), for operating themedical device 1200. In some embodiments, medical device 1200 mayrepresent the distal end of second longitudinal element 108 (referringto FIG. 1).

A pushing element 1208 may be disposed within a lumen 1210 defined byelongate member 1202. Pushing element 1208 may be coupled to actuator140 in any suitable manner. Pushing element 1208 may be advanceddistally by actuator 140 and may contact a fiducial 1212 disposed withina cartridge 1214. Cartridge 1214 may be disposed distal to pushingelement 1208 within lumen 1210 and may be configured to hold fiducials1212 in a plurality of chambers 1216 disposed in a radial arrangementabout cartridge 1214. In one embodiment, cartridge 1214 may include sixchambers 1216, though any other suitable number of chambers may beutilized, if desired. Fiducials 1212 may be substantially similar tofiducials 212 (referring to FIG. 2). Each fiducial 1212 may stay in achamber 1216 via, e.g., a friction fit, until a sufficient force isapplied by pushing member 1208.

In one exemplary embodiment, pushing element 1208 may be aligned with afirst chamber 1216. As pushing element 1208 is moved distally throughthe first chamber 1216 (e.g., by actuator 140 of FIG. 1), a firstfiducial 1212 disposed within first chamber 1216 may extend distallytoward an opening 1218 disposed at distal end 1206 of elongate member1202. In an alternative embodiment, cartridge 1214 may be movedproximally (while pushing member 1208 is held in place) to ejectfiducials 1212 from chambers 1216.

Cartridge 1214 may then be rotated so that pushing element 1208 isaligned with a second chamber 1216. In an alternative embodiment,pushing element 1208 may be rotated to align with second chamber 1216.

In yet another alternative embodiment, a plurality of pushing elements1208 may be aligned with an equal number of chambers 1216, such thateach pushing element 1208 is aligned with a corresponding chamber 1216.In this embodiment, each pushing element 1208 may be aligned with acorresponding actuating mechanism.

FIG. 14 depicts an actuating mechanism in accordance with an embodimentof the present disclosure. Medical device 1400 may include a proximalcap 1402, an elongate member 1404, and a plurality of threads 1406disposed along the length of elongate member 1404. This particularembodiment may allow for precision in the deployment of fiducials inaccordance with other embodiments of the present disclosure. In someembodiments, the length and geometry of threads 1406 may be configuredsuch that, e.g., one full rotation of proximal cap 1402 may deploy onefiducial from a distal end of a medical device. In some embodiments,medical device 1400 may represent actuator 140 of FIG. 1. In someembodiments, proximal cap 1402 may be moved distally to deploy fiducialsinto a patient's body, while in other embodiments, proximal cap 1402 maybe moved proximally to deploy the fiducials.

FIG. 15 depicts an actuating mechanism in accordance with an embodimentof the present disclosure. Medical device 1500 may include a proximalcap 1502, an elongate member 1504, and a protrusion 1506 extendingdistally from proximal cap 1502. Medical device 1500 may also include aplurality of seats configured to cooperate with protrusion 1506. Thisparticular embodiment may also allow for precision in the deployment offiducials in accordance with other embodiments of the presentdisclosure. In one embodiment, medical device 1500 includes three seats1508, 1510, and 1512. In some embodiments, a distally adjacent seat maybe transposed about the longitudinal axis of medical device 1500 withrespect to a proximally adjacent seat. For example, seat 1510 may bedistal to seat 1508 and may be transposed about the longitudinal axis ofmedical device 1500 in either a clockwise or counterclockwise direction.To deploy a first fiducial (not shown in FIG. 15), a user may rotate cap1502 so that protrusion 1506 is aligned with seat 1510, and then apply adistal force to cap 1502 so that protrusion 1506 and seat 1510 contacteach other or are otherwise coupled. The distance d traveled byprotrusion 1506 may be configured to deploy a precise number offiducials (e.g., one fiducial). In some embodiments, medical device 1500may represent actuator 140 of FIG. 1. To deploy a second fiducial (notshown in FIG. 15), the user may rotate cap 1502 so that protrusion 1506is aligned with seat 1512, and then apply a distal force to cap 1502 sothat protrusion 1506 and seat 1512 are coupled. While three seats aredepicted in the embodiment of FIG. 15, any suitable number of seats mayalternatively be utilized.

Any aspect set forth in any embodiment may be used with any otherembodiment set forth herein. Every device and apparatus set forth hereinmay be used in any suitable medical procedure, may be advanced throughany suitable body lumen and body cavity, and may be used to accesstissue from any suitable body portion. For example, the apparatuses andmethods described herein may be used through any natural body lumen ortract, including those accessed orally, vaginally, rectally, nasally,urethrally, or through incisions in any suitable tissue.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the disclosed systems andprocesses without departing from the scope of the invention. Otherembodiments of the disclosure will be apparent to those skilled in theart from consideration of the specification and practice of thedisclosure disclosed herein. It is intended that the specification andexamples be considered as exemplary only. The following disclosureidentifies some other exemplary embodiments.

We claim:
 1. A medical device, comprising: an elongate member having aproximal end and a distal end; a lumen disposed through the elongatemember; an opening disposed at the distal end of the elongate member incommunication with the lumen; a pushing element disposed with the lumen;a plurality of fiducials disposed within the lumen and distal to thepushing element; and a separating mechanism disposed at the distal endof the elongate member, the separating mechanism configured to apply aseparating force to deploy one fiducial of the plurality of fiducials asother fiducials of the plurality of fiducials remain disposed within thelumen.
 2. The medical device of claim 1, wherein the plurality offiducials are connected to each other by a linkage.
 3. The medicaldevice of claim 2, wherein the separating mechanism is configured todirect the separating force to a distal portion of the linkage to deploya distalmost fiducial.
 4. The medical device of claim 1, wherein: the atleast one fiducial is one of a plurality of fiducials disposed withinthe lumen; and adjacent fiducials of the plurality of fiducials aredisposed within compartments separated by spacers.
 5. The medical deviceof claim 4, wherein the separating mechanism is configured to apply theseparating force to a distalmost spacer to deploy a distalmost fiducial.6. A method of deploying multiple fiducials within a patient, the methodcomprising: advancing a medical device into a body lumen of the patient;applying a distally-directed force to direct at least one fiducialtoward an opening at a distal end of the medical device; and applying aseparating force, distinct from the distally-directed force, to deploythe fiducial.
 7. The method of claim 6, wherein the distally-directedforce is applied by a pushing element disposed within a lumen of themedical device.
 8. The method of claim 6, wherein the separating forceis one of an electric charge, heat, or a mechanical force.
 9. The methodof claim 6, wherein: the at least one fiducial is one of a plurality offiducials connected to each other by a linkage; and applying theseparating force to a distalmost portion of the linkage to deploy adistal fiducial.
 10. The method of claim 6, wherein: the at least onefiducial is one of a plurality of fiducials disposed within the lumen;adjacent fiducials of the plurality of fiducials are disposed withincompartments separated by spacers; and applying the separating force toa distalmost spacer to deploy a distalmost fiducial.
 11. The method ofclaim 6, further comprising applying the separating force to a distalend of a continuous length of fiducial material to form a plurality offiducials.
 12. A medical device, comprising: an elongate member having aproximal end and a distal end; a first lumen disposed through theelongate member; an opening disposed at the distal end of the elongatemember in communication with the lumen; a plurality of fiducialsdisposed within the first lumen; and at least one biasing elementdisposed within the first lumen proximal to the plurality of fiducials,the at least one biasing element configured to urge the plurality offiducials toward the opening after deployment of a distalmost fiducial.13. The medical device of claim 12, further comprising a distal openingmechanism disposed at the distal end of the elongate member, the distalopening mechanism configured to rotate about a joint to eject thedistalmost fiducial from the first lumen.
 14. The medical device ofclaim 12, further comprising: a second lumen disposed in the elongatemember parallel to the first lumen; a pushing element disposed throughthe second lumen, the pushing element being configured to reciprocallymove between a proximal loading position and a distal deploymentposition, wherein when the pushing element is in the proximal loadingposition and no fiducial is in the second lumen, a distalmost fiducialdisposed within the first lumen is urged toward the second lumen.